The invention pertains to a rotary piston machine in which a rotor rotates in an enclosure and radially movable slides in the rotor form chambers of varying volume between the enclosure and the rotor, wherein an even number of slides are provided and mutually opposing slides are joined together into a rigid unit.
Such a rotary piston machine is known from GB 430 715 B. Here the enclosure has the form of a Reuleaux triangle and the rotor is arranged centrally in the triangle. The advantage of such an arrangement over and above the use of one-sided spring-loaded slides is that in the rotation of the rotor, the enclosure wall need overcome only the inertial mass of the slide to move it back and forth while the centrifugal acceleration is at least essentially cancelled by the joining of the diametrically opposing slides, and spring forces that must always be provided for individual slides in order to press them against the wall in the first place can be completely eliminated.
Thus, a rotary piston machine of the type mentioned initially is subjected to considerably reduced wear in comparison to rotary piston machines with individually movable slides.
As more distant prior art pertaining to these other rotary piston machines that one can refer to, for instance, to DD-33 914 A in which the enclosure has a circular cross section, and the rotor arranged eccentrically in the enclosure likewise has an essentially circular cross section but with recesses bounded in cross section by a circular arc being cut out of the rotor in order to increase the size of the chambers formed. The (four) slides are each pressed outward from the rotor by springs against the enclosure wall, which, together with the centrifugal acceleration, leads to large contact pressures and high wear.
Despite its advantages over and above DD-A, it is disadvantageous in the rotary piston machine known from GB-B in that, because of the compulsorily prescribed shape of a Reuleaux triangle, the formation of three enclosure pockets is inevitable during rotation, each pocket forming by a slide an initially expanding and then again shrinking chamber between the slides. In internal combustion engines, for instance, this necessarily leads to the formation of 6-stroke systems with intervening cooling sections. Another disadvantage caused by this is that each slide is pushed radially back and forth three times during a rotation which in turn in the course of a rotation leads to relatively high acceleration peaks.